Framework and Assumptions Case ll:{=(Yt,X1 is an IID random sample .When {Zt}is IID,Assumption 3.2 becomes E(et X)= E(et X1,X2,...Xt;...,Xn) E(et X:) 0. Assumption 3.3 [Nonsingularity]: (a)The minimum eigenvalue of the KxK square matrixX'X=XX is nonsingular,and (b)with probability one, λmin(X'X)→oasn→o. Assumption 3.3(a)rules out multicollinearity among the (k+1)regres- sors in Xt.Multicollinearity refers to a situation in which two or more explanatory variables in a multiple regression model are linearly related. To be continued ADVANCED ECONOMETRICS Classical Linear Regression Model May11,2021 12ADVANCED ECONOMETRICS Classical Linear Regression Model May 11, 2021 12 Framework and Assumptions Case II: is an IID random sample Assumption 3.3 To be continued